Britain's Prince William has brought Prince George to meet his baby sister.

The Duke and Duchess of Cambridge with Prince George

The Duke and Duchess of Cambridge with Prince George

The 32-year-old royal carried his 21-month-old son into the Lindo Wing at St Mary's Hospital in West London to visit the Duchess of Cambridge and the little girl.

The pair stopped to wave to the waiting media and fans, some who have been camping outside the hospital for two weeks.

Only a few moments earlier, the Duke of Cambridge, wearing a blue jumper, was seen driving himself to Kensington Palace to pick up the future King where Prince William told the waiting media and fans that the couple were "very happy" with the new arrival.

Earlier today (02.05.15), the exciting news was confirmed via Twitter.

The announcement on Kensington Palace's official account read: "Her Royal Highness The Duchess of Cambridge was safely delivered of a daughter at 8.34am. The baby weighs 8lbs 3oz. The Duke of Cambridge was present for the birth.

"The Queen, The Duke of Edinburgh, The Prince of Wales & The Duchess of Cornwall, Prince Harry & members of both families have been informed. Her Royal Highness and her child are both doing well."

The baby girl will be fourth in line to the throne, behind her grandfather Prince Charles, her father Prince William and brother Prince George.